Visual function declines with age. Using extracellular single-unit in vivo recordings, we compared the function of primary visual cortical (area 17) cells in young and old paralyzed, anesthetized cats. The results reveal that cortical neurons in old cats exhibit higher visually evoked responses, higher spontaneous activities, lower signal-to-noise ratios, and weaker orientation and direction selectivity than do cells in young adult cats. These findings are consistent with previously reported age related declines in cortical function in senescent macaque monkeys. Thus, similar declines in cortical function accompany old age in different mammalian species with well developed cortices.
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http://dx.doi.org/10.1016/j.neurobiolaging.2004.11.012 | DOI Listing |
Sci Rep
January 2025
Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC, Canada.
People with amblyopia show deficits in global motion perception, especially at slow speeds. These observers are also known to have unstable fixation when viewing stationary fixation targets, relative to healthy controls. It is possible that poor fixation stability during motion viewing interferes with the fidelity of the input to motion-sensitive neurons in visual cortex.
View Article and Find Full Text PDFJ Shoulder Elbow Surg
January 2025
Department of Orthopedics and Trauma, Peking University People's Hospital, Beijing 100044, China; Key Laboratory of Trauma and Neural Regeneration (Peking University), Ministry of Education, Beijing 100044, China; National Center for Trauma Medicine, Peking University People's Hospital, Beijing 100044, China. Electronic address:
Objective: The bare area is defined as a transverse region within the trochlear notch, serving as an optimal entry point for olecranon osteotomy due to the absence of articular cartilage coverage. However, there is limited research on the morphology and location of the bare area, and there is a lack of intuitive visual description. Thus, the purpose of this study is to delineate anatomical features of the bare area and visualize its morphology and refine the olecranon osteotomy approach.
View Article and Find Full Text PDFNeuroimage
January 2025
Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada; Department of Physiology, McGill University, Montreal, Quebec, Canada. Electronic address:
In response to sensory deprivation, the brain adapts to efficiently navigate a modified perceptual environment through a process referred to as compensatory crossmodal plasticity, allowing the remaining senses to repurpose deprived regions and networks. A mechanism that has been proposed to contribute to this plasticity involves adaptations within subcortical nuclei that trigger cascading effects throughout the brain. The current study uses 7T MRI to investigate the effect of perinatal deafness on the volumes of subcortical structures in felines, focusing on key sensory nuclei within the brainstem and thalamus.
View Article and Find Full Text PDFJ Integr Neurosci
January 2025
Neuroscience Department, University of Connecticut Health, School of Medicine, Institute for Systems Genomics, Farmington, CT 06030, USA.
Background: In neuroscience, Ca imaging is a prevalent technique used to infer neuronal electrical activity, often relying on optical signals recorded at low sampling rates (3 to 30 Hz) across multiple neurons simultaneously. This study investigated whether increasing the sampling rate preserves critical information that may be missed at slower acquisition speeds.
Methods: Primary neuronal cultures were prepared from the cortex of newborn pups.
Medicina (Kaunas)
December 2024
Second Department of Internal Medicine, "Victor Babes" University of Medicine and Pharmacy, 300041 Timisoara, Romania.
Diabetes has become a global epidemic, contributing to significant health challenges due to its complications. Among these, diabetes can affect sight through various mechanisms, emphasizing the importance of early identification and management of vision-threatening conditions in diabetic patients. Changes in the crystalline lens caused by diabetes may lead to temporary and permanent visual impairment.
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